Apparatus for drying and handling bagasse and similar materials



June 22 1926. 1,589,805

W. KAJERDT ET AL APPARATUS FOR DRYING AND HANDLING BAGASSE AND SIMILAR MATERIALS Original Filed March 20, 1922 2 Sheets-Sheet 1 gvwewtow @3313 w elf lime 5 r June 22 1926. 1,589,805

w. KAJERDT ET AL APPARATUS FOR DRYING AND HANDLING BAGASSE AND SIMILAR MATERIALS Original Filed March 20, 1922 2 Sheets-Sheet 2 Patented June 22, 1926.

UNITED STATES PATENT OFFICE.

APPARATUS FOR DRYING AND HANDLING BAGASSE AND SIMILAR MATERIALS.

Application filed March 20, 1922, Serial No. 545,382. Renewed April 26, 1926.

Our invention finds its most useful application in plants for'grinding sugar cane, in which plants it is desirable to use the more fibrous portion of the cane left after the juice has been pressed out of it, as fuel under the boilers which generate power for driving the press rolls and other machlnery. This waste product is known as bagasse, and

as it comes from the press rolls it contains considerable moisture. To make it an efficient fuel this moisture must be taken out. By our invention the waste heat of the gases of combustion from the boiler furnaces is most efliciently employed for so drying the ll bagasse. The best form of apparatus for this purpose at present known to us, embodying our invention, is illustrated in the accompanying two sheets of drawings, in which- 80 Fig. 1 is an elevation partly in section and partly diagrammatic, showing the apparatus assembled;

Fig. 2 is an enlarged detail view of apparatus for regulating the temperature of I the drying gases, being a longitudinal section on a vertical plane; and

Figs. 3 and 4 are cross-sections taken on lines 33 and 4-4, respectively, of Fig. 2.

Throughout the drawings like reference characters indicate like parts.

i represents diagrammatically the last set of rolls to which the sugar cane is delivered through chute 11. Theba asse passes out from the rolls in the direction indicated by to the arrows and drops on the deck 4 of the endless chain conveyor composed of the endless chains 2, carrying blades or scrapers 3, 3, said chains being driven in a clockwise direction by the'crossed belt from motor to 20. .The bagasse is carried up along deck 4, and drops through the opening 6, between deck sections 4 and 5, into the hop r 7. The outlet from this hopper is control ed by the counterweighted gate or trap 8. When W a predetermined amount of bagasse has accumulated in the hopper 7, its weight is suficient to trip gate 8 and said bagasse is then dropped into the suction conduit 9 of blower 19. Normally the gate being W closed, prevents access of air to said conduit 9 through hopper 7.

A The normal supply of gases to blower 19 is delivered to conduit 9 froin the flue 10 for the hot gases from the furnaces of the the various boiler furnaces and to a chimney (not shown). sparks, etc., to the conduit 9, we place a series-of wire cloth screens 12 across the conduit 9 near its connection to the flue 10, as shown. To regulate the temperature of the gases in the conduit before they reach the bagasse, and so avoid possibility of scorching or burning it in the apparatus, we provide the cold'air inlet 13, to the conduit 9, which inlet is controlled by damper 14 mounted on shaft 15. This damper 1s regulated by any suitable thermostatic apparatus located in the suction conduit between the coldair inlet 13 and the point at which the bagasse is delivered to said conduit. A convenient form ofsuch thermostatic control is illustrated in Figs. 2, 3 and 4, in which a rock-arm 16 on the inner end of shaft 15, is connected to the free ends of curved strip 17 formed of two metals having different coeficients of expansion, such as an inner'strip of iron and an outer strip of aluminum. This thermostatic element is anchored to, and supported from, the strap 18 extending across the bottom of the con- To prevent access of cinders,

duit. The parts are so proportioned and adjusted that when the mixture of hot flue gases with the cold air admitted through inlet 13 by a given setting of damper 14, has the predetermined temperature, the thermostatic element 17 .will be in equilibrium. If

then the furnaces deliver any hotter volume of gases to flue 10, the thermostatic element will'expand and swing the damper 14 so as to more widely open air inlet 13 and further dilute said hot gases with atmospheric air to an extent which will nearly restore the predetermined temperature of the mixture delivered to the blower. If, on the other hand. the temperature of the flue ases falls, the reverse operation occurs an the suppl of atmospheric air is reduced, so that t e temperature of the mixture is again stabilized.

The mixture of hot gases and hagasse formed in conduit 9, passes through the blower 19 and is delivered, through any suitable conduit, to a separating device .which will allow the'excess air to escape to the atm here while the dried bagasse, from whic' the moisture has been evaporated by contact with the hot gases, is passed out through a separate connection for delivery to the furnaces. We have illustrated a convenien f rm of such apparatus comllll prising the uptake 22, leading from the discharge port of blower 19 (which blower is driven by belt 2]. from motor 20) to the cyclone separator 23. This cyclone separator may be of a standard type or it may be provided with a helical strip or'ribbon 24 aflixed to its interior walls so as to form a circumferential, helical passageway, open toward the center, down which passageway the bagasse passes slowly by gravity while still exposed to the action of the circulating body of escaping hot gases. 25 is a chute connected to the bottom of the separating device in which chute the dried'bagasse accumulates until its weight becomes sufficient to open counterweighted gate or trap 26. Thereupon it drops on the upper section 5 of the conveyor deck and is delivered therefrom to the transverse, distributing conveyor belt 27, from which it may drop into the feed chute 28 of any particular furnace which requires additional fuel. After each intermittent discharge action of gate 26 it closes automatically and so prevents further escape of bagasse or gases from the separator until a sufiicient weight of collected bagasse again trips it.

The advantages of our invention comprise its simplicity and economy of operation, the waste gases of the furnaces being utilized in an efiicient manner to dry the fuel to be used in the furnaces.

The blades of the blower 19, which is preferably of the fan type, act as stirrers to separate the bagasse fibres and expose them to the evaporating action of the hot gases with which they are intimately mixed by this same beater action of the blades.

It is evident that other forms of blowers, conveyors, thermostats, dampers, automatic gates, flues and connections could be substituted for those here illustrated and described, so long as they are properly proportioned and coordinated to operate in accordance with the underlying principles of our invention as above explained.

Having described our invention, we claim:

1. In an apparatus for drying bagasse and similar materials the combination, with a blower and means for driving the same, of means for supplying heated gases to said blower, thermostatic means for controlling the temperature of said gases, means for delivering bagasse to the intake of the blower, adischarge conduit from the blower through which said bagasse may be driven by the current of heated gases also delivered bythe blower, an apparatus for separating said-'bagasse from-said heated gases, and mech n s or d har g t d gasse from said separating apparatus.

:1 lapp a n for nv bagasse and-similarmateri'als the combination of a blower, a pipe connected to. the intake of said blower, means for previously heating gases, supplying them to the intake end of said pipe and mixing them therein with bagasse, thermostatic means for controlling the volume of heated gases so supplied, and a discharge pipe from said blower for conveying away therefrom the bagasse dried by said heated gases.

3. In an apparatus for drying and feeding bagasse to a furnace, the combination, with such furnace and the flue for the gases of combustion drawn therefrom, of a blower,'-a conduit extending from said flue to the blower intake, apparatus for introducing the bagasse into said conduit, a device for separating the bagasse from the said gases, a. conduit extending from the discharge port of the blower to said device, and mechanism for conveying the bagasse from the separating device to the furnace.

4. In an apparatus for handling and drying bagasse and similar materials, the combination. with a blower and means for driving it, of a conduit connected to the blower inlet, means for supplying hot gases to said conduit, an air inlet to said conduit, a damper for said inlet, a thermostat in said conduit operatively connected to said damper, a

hopper connected to said conduit between said thermostat and the blower, and means in said hopper connection intermittently operating to discharge bagasse from the hopper into the conduit but normally preventing the passage of air through said hopper to said conduit.

5. In an apparatus for drying bagasse and similar materials the combination, with a blower and means for delivering hot gases and bagasse to the intake of said blower, of a cyclone separator located above the blower, connected to the discharge port thereof and provided with a downwardly extending discharge conduit for the bagasse, said discharge conduit having a counterweighted gate normally closed but adapted to open and discharge the'bagasse when a predetermined weight thereof has accumulated 1n the conduit.

6. In an apparatus for drying bagasse, the combination of a cyclone separator, means for delivering the dried bagasse to said separator, and a downwardly extending discharge conduit for the bagasse from said separator, which conduit has a counterweighted gate normally closed but adaptedto open when a predetermined weight of the bagasse accumulates in said conduit.

7. In an apparatus for drying bagasse and similar materials, the combination, with a blower and means for delivering hot gases and bagasse to the intake of said blower,'of a. cyclone separator located above and connected to the discharge port of the blower, which said separator is provided with a downwardly extending discharge conduit for the bagass e having a counter-weighted 'sageway, open toward the center, and exgate normally closed but adapted to open tending from the inlet of the separator and discharge the bagasse when a prededownward toward the outlet for the dried termined weight thereof has accumulated in material. 5 the conduit, and is also provided with a helically disposed ribbon of metal attached WILLIAM KAJERDT.

to its inner wall and forming a helical pas- MARIANO J GALAINENA. 

